See Blackbird Bikes and Quadribent side-by-side recumbent bicycles at events, on TV, and in the newspapers

Viola Carlson, 91, and Barbara Mattson, 65, are a mother and daughter who have found a way to keep active together, thanks to the Quadribent Side-by-Side Recumbent Bikes, a system invented by a Minnesotan that attaches two EZ-Classic recumbent bikes to make a "Sociable Tandem."